//5.数组
let arr:number[]=[10,20,30,40];
    arr.push(50);
    // arr.push("zifuchuang");//error
let arr2:string[]=["王五","马六","张三"];
    // arr2.push(29);//Error
//泛型数组写法
let arr3:Array<number>=[1,2,3,4];
    arr3.push(99);
    // arr3.push(true);//Error
//6.元组  数组的数据类型数据长度是确定已知的.
let tuple1:[string,number,boolean];
    // tuple1=["laoxie",18];//error 个数不匹配
    tuple1=["老谢",18,true];